Effect of different miniplate osteosynthesis in different mandibular angle fracture patterns on bite force: A 3D finite element analysis

Comparison of bite force evaluation for mandibular angle fracture fixation by conventional miniplates versus new design miniplates: a clinical study

PURPOSE

To evaluate postoperative masticatory efficacy of a new design non-compression titanium miniplate compared to conventional non-compression titanium miniplate on the basis of bite force for treatment of mandibular angle fractures.

METHODOLOGY

The prospective study included 20 patients with mandibular angle fractures randomly categorized into 2 groups: Group I, fixation of angle fractures by conventional miniplates, and Group II, fixation of angle fractures by new design miniplates. Evaluation was done for clinical outcome, primarily bite force; radiological outcome; and associated postoperative morbidities at different time intervals.

RESULTS

The results showed to be highly significant in terms of mean operating time for plate adaptation and fixation and bite force adaptation (p = 0.003 at follow-up of 6 months) for the newer miniplate compared to the conventional miniplate. No statistically significant difference was seen for postoperative paresthesia, malunion, non-union, occlusal discrepancy, or hardware failure.

CONCLUSION

Within the limits of the study, it appears that the single, monocortical, non-compression, superior border new design miniplate proved to be a successful procedure for treating non-comminuted mandibular angle fractures specifically in terms of enhanced postoperative masticatory efficiency as compared to conventional miniplates. Further clinical studies with larger sample size can derive a more comprehensive conclusion.

The comparison between various methods of mandibular reconstruction based on finite element analysis

The Mandible can be damaged by pathological factors, tumors, trauma, infection, and needs a surgical operation for reconstruction and restoring function. There are different methods for the reconstruction of mandible. Based on the surgical approach, primary reconstruction of mandible by reconstruction plate after resection is necessary for maintaining mandibular symmetric and esthetic of the lower third of the face. A finite element model of mandible and masticatory muscles was produced from a normal person (male with 35-year-old). The normal model was resected from the left sixth tooth to the second tooth. The pathological model was reconstructed in different conditions by macro plate. Different conditions were analyzed and compared based on bite force on right fifth tooth, stress developed on screws and macro plate. The finite element analysis results showed that maximum bite force and lower stress on screws were seen in the pathological model (condition 5) when one macro plate and six screws were inserted in the mid-body. The findings showed that the use of two macro plates causes lower stress on it than when we use one. Use of one macro plate and six screws is the best choice in mandibular immobilization which decrease the stress applied on bone and increase the bite force. Because of less stress developed on macro plates and screws, use of two macro plates or one macro plate in mid-body area are also preferred.